Food patty molding machines are commonly employed for centralized manufacture of hamburger patties, chicken patties, fish patties, imitation steaks, and a variety of other molded patties of different food products. Three practical and efficient food patty molding machines that have enjoyed substantial commercial success are those described in U.S. Pat. Nos. Re. 30,096, to Richards et al, 4,054,967 to Sandberg et al and 4,182,003, to Lamartino et al. which are available as the F-26, F-19, and F-12 food patty molding machines, respectively, made and sold by Formax, Inc. of Mokena, Ill. The smallest of these machines, the Formax F-12 machine, is rather large for use by an individual restaurant or other establishment selling molded food patties directly to the consumer. On the other hand, other manufacturers have regularly produced food patty molding machines that are small enough to be effectively used in an individual restaurant or other food retail establishment.
It may be necessary or desirable to interleave individual paper sheets with the food patties produced by any food patty molding machine, whether large or small. A variety of different mechanisms for interleaving paper sheets with molded food patties, directly at the output of a food patty molding machine have been proposed. With respect to the Formax machines identified above, the most successful paper interleaver mechanism has been that described in Richards et al U.S. Pat. No. 3,952,478.
There are certain basic, recurring problems that appear in connection with most paper interleavers as applied to food patty molding machines. To begin with, the paper interleavers almost invariably function at the knock-out station of the patty molding machine, where the food patties are displaced from a cyclically operating mold plate with each patty engaging its paper sheet as it falls from the mold plate onto a takeaway conveyor. The knock-out station of the food patty molding machine is not a clean, pristine environment. Individual food product particles are frequently dislodged from patties during the knock-out operation. Juices produced by the molded food patties are almost inevitably present. As a consequence, those paper interleavers that employ vacuum positioning devices to hold the paper sheets in place for contact by the falling food patties are subject to clogging and blockage from the food particles and juices originating from the patties themselves. This presents a substantial and continuing problem and makes it quite difficult to maintain the paper interleavers in continuous operation.
Another common problem that occurs in the paper interleavers used with food patty molding machines is double-sheeting. If the paper supply for the interleaver is in an unrestrained stack, most conventional pickup mechanisms will occasionally pick up two or even more sheets. Double-sheeting may be less common where the paper supply is a restrained one with all of the paper sheets mounted on a spindle, but can still occur. For a spindle type paper supply, however, unwanted paper particles are frequently produced when individual sheets are pulled from the stack and the portion of the paper immediately adjacent the spindle hole is often distorted.